DOCUMENTATION.md

Documentation

Important Files

File	Description
ansible.cfg	Ansible configuration file.
group_vars/*	Variables for local staging and productive DNS resolvers. Also contains the specific vault.yml files (these are not part of this repository)
host_vars/*	Variables specific to Ansible controlled host.
inventory.yml	Productive DNS resolver hostnames referencing entries in the local ./ssh/config hostnames.
local.yml	Local staging DNS resolver hostnames referencing entries in the local ./ssh/config hostnames.
resolver.yml	This is the actual Ansible playbook. It specifies what roles shall be applied to what hosts.
scripts/local-lxc-setup.sh	Helper script to start a local setup based on lxc linux ubuntu containers.

Roles

Role	Description
base	Basic server setup, user configuration, tool and package installation for basic server management.
dns-backend	Backend DNS resolver configuration, communicates with the domain name system (the Internet).
dns-frontend	Frontend DNS resolver configuration, encrypted communicates with the users who use our service.
high-availability	VRRP configuration providing high availability between DNS resolvers.
monitoring	The server-side and third-party-side monitoring of our DNS resolvers.
web-server	Responsible for creating Let's Encrypt certificates and reverse proxy for monitoring purposes.

Ansible Variables

Variable name	Description
dg4_dns	IP v4 default gateway
dg6_dns	IP v6 default gateway
dnsdist_nof_thread_doh_per_ip	Number of dnsdist threads per DoH IP
dnsdist_nof_thread_dot_per_ip	Number of dnsdist threads per DoT IP
dnsdist_nof_thread_upstream	Number of dnsdist upstream threads
domain	Domain of this resolver
host_public	Hostname of this resolver
if_loopback	Name of the loopback interface on this server
if_primary	Name of the primary interface on this server
ip4_dns1	Public IP v4 address of resolver 1
ip4_dns2	Public IP v4 address of resolver 2
ip4_vip_dns1	Public IP v4 address of resolver 1
ip4_vip_dns2	Public IP v4 address of resolver 2
ip4_vrrp1	Internal VRRP (load balancing) IP v4 address of resolver 1
ip4_vrrp2	Internal VRRP (load balancing) IP v4 address of resolver 2
ip6_dns1	Public IP v6 address of resolver 1
ip6_dns2	Public IP v6 address of resolver 2
ip6_vip_dns1	Public IP v6 address of resolver 1
ip6_vip_dns2	Public IP v6 address of resolver 2
ip6_vrrp1	Internal VRRP (load balancing) IP v6 address of resolver 1
ip6_vrrp2	Internal VRRP (load balancing) IP v6 address of resolver 2
ip_localhost	IP v4 of the loopback interface on this server
netmask4_dns_cidr	Netmask of the public IP v4
netmask4_vrrp1_cidr	Netmask of the internal VRRP (load balancing) IP v4
netmask6_dns_cidr	Netmask of the public IP v6
netmask6_vrrp1_cidr	Netmask of the internal VRRP (load balancing) IP v6
network_port_ssh	Custom SSH tcp port
node_exporter_web_listen_address	Node exporter listening host and port
nof_cpu	Number of CPUs of this resolver
unbound_msg_cache_size	Unbound message cache size in bytes
unbound_nof_slabs	Unbound number of slabs
unbound_nof_thread	Unbound number of Unbound threads
unbound_num_queries_per_thread	Unbound number of queries per thread
unbound_outgoing_range	Unbound outgoing range
unbound_rrset_cache_size	Unbound RR cache size in bytes
unbound_so_rcvbuf	Unbound SO receive buffer size in bytes
unbound_so_sndbuf	Unbound SO send buffer size in bytes
vip_interfaces	List of virtual IP v4 and v6 addresses